Liquid crystal display device and method for fabricating the same

ABSTRACT

A liquid crystal display (LCD) device capable of preventing impurities from permeating into a channel area of a switching element, the LCD device including: a gate electrode above a substrate; a semiconductor layer which overlaps the gate electrode; a drain electrode and a source electrode which overlap the semiconductor layer; an ohmic contact layer between the semiconductor layer and the drain electrode and between the semiconductor layer and the source electrode; a pixel electrode which is connected to one of the drain electrode and the source electrode; and a gate insulating layer between the gate electrode and the semiconductor layer, the gate insulating layer comprising fluorine. A concentration of the fluorine is decreasing, as the fluorine of the gate insulating layer being more adjacent to the substrate.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2016-0007047, filed on Jan. 20, 2016, with the KoreanIntellectual Property Office, the disclosure of which is incorporatedherein in its entirety by reference.

BACKGROUND

1. Field

Aspects of embodiments of the present inventive concept relate to aliquid crystal display (LCD) device capable of preventing impuritiesfrom diffusing into a channel area of a switching element and to amethod of manufacturing the LCD device.

2. Description of the Related Art

An LCD device is a type of a flat panel display (FPD) which has becomewidely used in various applications recently. An LCD device includes twosubstrates respectively including two electrodes formed thereon and aliquid crystal layer interposed therebetween. Upon applying voltage tothe two electrodes of the LCD device, liquid crystal molecules of theliquid crystal layer are rearranged such that an amount of transmittedlight may be adjusted.

An LCD device includes a plurality of pixels, and each of the pluralityof pixels includes a switching element, e.g., a thin film transistor(TFT), which applies a data voltage to a pixel electrode.

In a process of manufacturing a conventional switching element,impurities generated in an impurity semiconductor material diffused intoa channel area of the switching element, thus causing an issue ofincreased leakage current in the switching element.

It is to be understood that this background of the technology section isintended to provide useful background for understanding the technologyand as such disclosed herein, the technology background section mayinclude ideas, concepts or recognitions that were not part of what wasknown or appreciated by those skilled in the pertinent art prior to acorresponding effective filing date of subject matter disclosed herein.

SUMMARY

Aspects of embodiments of the present inventive concept are directed toa liquid crystal display (LCD) display device capable of preventingimpurities from permeating into a channel area of a switching elementand to a method of manufacturing the LCD display device.

According to an embodiment of the present inventive concept, a liquidcrystal display device includes: a gate electrode above a substrate; asemiconductor layer which overlaps the gate electrode; a drain electrodeand a source electrode which overlap the semiconductor layer; an ohmiccontact layer between the semiconductor layer and the drain electrodeand between the semiconductor layer and the source electrode; a pixelelectrode which is connected to one of the drain electrode and thesource electrode; and a gate insulating layer between the gate electrodeand the semiconductor layer, the gate insulating layer comprisingfluorine A concentration of the fluorine is decreasing, as the fluorineof the gate insulating layer being more adjacent to the substrate.

The ohmic contact layer may have an impurity concentration of about2*10²¹ atom/cm³ or higher.

The fluorine is not included in the gate insulating layer correspondingto a center of a channel area which is disposed between the sourceelectrode and the drain electrode.

The ohmic contact layer may contact the gate insulating layer.

The ohmic contact layer may include: a first ohmic contact layer betweenthe drain electrode and the gate insulating layer, the first ohmiccontact layer contacting the gate insulating layer; and a second ohmiccontact layer between the source electrode and the gate insulatinglayer, the second ohmic contact layer contacting the gate insulatinglayer.

The first ohmic contact layer may be further disposed between the gateinsulating layer and the data line which is connected to the drainelectrode.

The semiconductor layer has substantially the same thickness as athickness of a thickest portion of a non-channel area of thesemiconductor layer.

A second surface of the semiconductor layer which is opposite to a firstsurface of the semiconductor layer is substantially flat, the firstsurface of the semiconductor layer facing the gate insulating layer.

According to an embodiment of the present inventive concept, a method ofmanufacturing a liquid crystal display device includes: forming a gateelectrode above a substrate; forming a gate insulating layer above thegate electrode; forming a semiconductor material above the gateinsulating layer; forming a first photoresist pattern and a secondphotoresist pattern above the semiconductor material, the secondphotoresist pattern having a smaller thickness than a thickness of thefirst photoresist pattern; patterning, using the first photoresistpattern and the second photoresist pattern as a mask, the semiconductormaterial to form a semiconductor layer which overlaps the gateelectrode; removing a portion of the first photoresist pattern and thesecond photoresist pattern to form a third photoresist pattern which isdisposed to correspond to a channel area of the semiconductor layer;hydrophobizating the third photoresist pattern; forming an impuritysemiconductor material above the gate insulating layer and thesemiconductor layer using the third photoresist pattern that ishydrophobizated as a mask; removing the third photoresist pattern;forming a conductive material above the impurity semiconductor materialand the semiconductor layer; patterning, using a fourth photoresistpattern as a mask, the impurity semiconductor material and theconductive material to form a first ohmic contact layer, a second ohmiccontact layer, a drain electrode, and a source electrode; and forming apixel electrode which is connected to one of the drain electrode and thesource electrode.

The hydrophobizating of the third photoresist pattern may includeexposing the third photoresist pattern to NF₃.

Each of the first ohmic contact layer and the second ohmic contact layermay have an impurity concentration of about 2*10²¹ atom/cm³ or higher.

The forming of the first ohmic contact layer, the second ohmic contactlayer, the drain electrode, and the source electrode may include:forming the fourth photoresist pattern above the conductive material;and patterning, using the fourth photoresist pattern as a mask, theconductive material and the impurity semiconductor material in a wetetching method to form the first ohmic contact layer, the second ohmiccontact layer, the drain electrode, and the source electrode.

According to another embodiment of the present inventive concept, amethod of manufacturing a liquid crystal display device includes:forming a gate electrode above a substrate; forming a gate insulatinglayer above the gate electrode; forming a semiconductor material abovethe gate insulating layer; forming a first photoresist pattern and asecond photoresist pattern above the semiconductor material, the secondphotoresist pattern having a smaller thickness than a thickness of thefirst photoresist pattern; patterning, using the first photoresistpattern and the second photoresist pattern as a mask, the semiconductormaterial to form a semiconductor layer which overlaps the gateelectrode; removing a portion of the first photoresist pattern and thesecond photoresist pattern to form a third photoresist pattern which isdisposed to correspond to a channel area of the semiconductor layer;forming an impurity semiconductor material above the gate insulatinglayer, the semiconductor layer, and the third photoresist pattern;removing the third photoresist pattern and the impurity semiconductormaterial above the third photoresist pattern in a lift-off method;forming a conductive material above the impurity semiconductor materialand the semiconductor layer; patterning, using a fourth photoresistpattern as a mask, the impurity semiconductor material and theconductive material to form a first ohmic contact layer, a second ohmiccontact layer, a drain electrode, and a source electrode; and forming apixel electrode which is connected to one of the drain electrode and thesource electrode.

Each of the first ohmic contact layer and the second ohmic contact layermay have an impurity concentration of about 2*10²¹ atom/cm³ or higher.

The forming of the first ohmic contact layer, the second ohmic contactlayer, the drain electrode, and the source electrode may include:forming the fourth photoresist pattern above the conductive material;and patterning, using the fourth photoresist pattern as a mask, theconductive material and the impurity semiconductor material in a wetetching method to form the first ohmic contact layer, the second ohmiccontact layer, the drain electrode, and the source electrode.

According to still another embodiment of the present inventive concept,a method of manufacturing a liquid crystal display device includes:forming a gate electrode above a substrate; forming a gate insulatinglayer above the gate electrode; forming a semiconductor material abovethe gate insulating layer; forming a first photoresist pattern above thesemiconductor material; patterning, using the first photoresist patternas a mask, the semiconductor material to form a semiconductor layerwhich overlaps the gate electrode; hydrophobizating the firstphotoresist pattern; forming an impurity semiconductor material above aninclined surface of the semiconductor layer and the gate insulatinglayer using the first photoresist pattern that is hydrophobizated as amask; removing the first photoresist pattern; forming a conductivematerial above the impurity semiconductor material and the semiconductorlayer; patterning, using a second photoresist pattern as a mask, theimpurity semiconductor material and the conductive material to form afirst ohmic contact layer, a second ohmic contact layer, a drainelectrode, and a source electrode; and forming a pixel electrode whichis connected to one of the drain electrode and the source electrode.

The hydrophobizating of the first photoresist pattern may includeexposing the first photoresist pattern to NF₃.

Each of the first ohmic contact layer and the second ohmic contact layermay have an impurity concentration of about 2*10²¹ atom/cm³ or higher.

The forming of the first ohmic contact layer, the second ohmic contactlayer, the drain electrode, and the source electrode may include:forming a third photoresist pattern above the conductive material; andpatterning, using the third photoresist pattern as a mask, theconductive material and the impurity semiconductor material in a wetetching method to form the first ohmic contact layer, the second ohmiccontact layer, the drain electrode, and the source electrode.

The foregoing is illustrative only and is not intended to be in any waylimiting. In addition to the illustrative aspects, embodiments, andfeatures described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and aspects of the present disclosure ofinventive concept will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a plan view illustrating a pixel according to an exemplaryembodiment;

FIG. 2 is a cross-sectional view taken along line I-I′ of FIG. 1;

FIG. 3 is a cross-sectional view taken along line II-IP of FIG. 1;

FIG. 4 is a cross-sectional view taken along line III-III′ of FIG. 1;

FIG. 5 is a view separately illustrating a first sub-pixel electrode ofFIG. 2;

FIG. 6 is a view illustrating two adjacent pixels having a structuredescribed in FIG. 1;

FIGS. 7A, 7B, 7C, 7D, 7E, 7F, 7G, 7H, 7I, 7J, 7K, 7L, 7M, 7N, 7O, and 7Pare cross-sectional views illustrating a process of manufacturing an LCDdevice according to an exemplary embodiment;

FIGS. 8A, 8B, 8C, 8D, and 8E are cross-sectional views illustrating aprocess of manufacturing an LCD device according to another exemplaryembodiment; and

FIGS. 9A, 9B, 9C, 9D, 9E, 9F, 9G, and 9H are cross-sectional viewsillustrating a process of manufacturing an LCD device according to stillanother exemplary embodiment.

DETAILED DESCRIPTION

Exemplary embodiments will now be described more fully hereinafter withreference to the accompanying drawings. Although the inventive conceptcan be modified in various manners and have several embodiments,exemplary embodiments are illustrated in the accompanying drawings andwill be mainly described in the specification. However, the scope of theinventive concept is not limited to the exemplary embodiments and shouldbe construed as including all the changes, equivalents, andsubstitutions included in the spirit and scope of the inventive concept.

In the drawings, certain elements or shapes may be illustrated in anenlarged manner or in a simplified manner to better illustrate theinventive concept, and other elements present in an actual product mayalso be omitted. Thus, the drawings are intended to facilitate theunderstanding of the present inventive concept.

When a layer, area, or plate is referred to as being “on” another layer,area, or plate, it may be directly on the other layer, area, or plate,or intervening layers, areas, or plates may be present therebetween.Conversely, when a layer, area, or plate is referred to as being“directly on” another layer, area, or plate, intervening layers, areas,or plates may be absent therebetween. Further when a layer, area, orplate is referred to as being “below” another layer, area, or plate, itmay be directly below the other layer, area, or plate, or interveninglayers, areas, or plates may be present therebetween. Conversely, when alayer, area, or plate is referred to as being “directly below” anotherlayer, area, or plate, intervening layers, areas, or plates may beabsent therebetween.

The spatially relative terms “below”, “beneath”, “less”, “above”,“upper”, and the like, may be used herein for ease of description todescribe the relations between one element or component and anotherelement or component as illustrated in the drawings. It will beunderstood that the spatially relative terms are intended to encompassdifferent orientations of the device in use or operation, in addition tothe orientation depicted in the drawings. For example, in the case wherea device shown in the drawing is turned over, the device positioned“below” or “beneath” another device may be placed “above” anotherdevice. Accordingly, the illustrative term “below” may include both thelower and upper positions. The device may also be oriented in the otherdirection, and thus the spatially relative terms may be interpreteddifferently depending on the orientations.

Throughout the specification, when an element is referred to as being“connected” to another element, the element is “directly connected” tothe other element, or “electrically connected” to the other element withone or more intervening elements interposed therebetween. It will befurther understood that the terms “comprises,” “comprising,” “includes”and/or “including,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

It will be understood that, although the terms “first,” “second,”“third,” and the like may be used herein to describe various elements,these elements should not be limited by these terms. These terms areonly used to distinguish one element from another element. Thus, “afirst element” discussed below could be termed “a second element” or “athird element,” and “a second element” and “a third element” can betermed likewise without departing from the teachings herein.

“About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” can mean within one or morestandard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

Unless otherwise defined, all terms used herein (including technical andscientific terms) have the same meaning as commonly understood by thoseskilled in the art to which this inventive concept pertains. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an ideal or excessively formal sense unlessclearly defined in the present specification.

Hereinafter, an exemplary embodiment of a liquid crystal display (LCD)device and a method of manufacturing the LCD device will be describedwith reference to FIGS. 1 to 9H.

FIG. 1 is a plan view illustrating a pixel according to an exemplaryembodiment, FIG. 2 is a cross-sectional view taken along line I-I′ ofFIG. 1, FIG. 3 is a cross-sectional view taken along line II-II′ of FIG.1, and FIG. 4 is a cross-sectional view taken along line III-III′ ofFIG. 1.

The LCD device, as illustrated in FIGS. 1, 2, 3, and 4, includes a firstsubstrate 301, a gate line GL, a first gate electrode GE1, a second gateelectrode GE2, a third gate electrode GE3, a first storage electrode751, a storage line 750, a second storage electrode 752, a gateinsulating layer 311, a first semiconductor layer 321, a secondsemiconductor layer 322, a third semiconductor layer 323, a first ohmiccontact layer 321 a, a second ohmic contact layer 321 b, a data line DL,a first drain electrode DE1, a first source electrode SE1, a seconddrain electrode DE2, a second source electrode SE2, a third drainelectrode DE3, a third source electrode SE3, a passivation layer 320, acapping layer 391, a color filter 354, pixel electrodes PE1 and PE2, asecond substrate 302, a light blocking layer 376, an overcoat layer 722,a common electrode 330, and a liquid crystal layer 333. Herein, thepixel electrodes PE1 and PE2 include a first sub-pixel electrode PE1disposed in a first sub-pixel area P1 and a second sub-pixel electrodePE2 disposed in a second sub-pixel area P2.

The first switching element TFT1, as illustrated in FIGS. 1 and 2,includes the first gate electrode GE1, the first semiconductor layer321, the first drain electrode DE1, and the first source electrode SE1.

The second switching element TFT2, as illustrated in FIGS. 1 and 3,includes the second gate electrode GE2, the second semiconductor layer322, the second drain electrode DE2, and the second source electrodeSE2.

As illustrated in FIGS. 1 and 2, the gate line GL is disposed above thefirst substrate 301. For example, the gate line GL is disposed betweenthe first sub-pixel area P1 and the second sub-pixel area P2 of thefirst substrate 301 in a plan view.

The gate line GL, as illustrated in FIGS. 1, 2, 3, and 4, is connectedto the first gate electrode GE1, the second gate electrode GE2, and thethird gate electrode GE3. The gate line GL, the first gate electrodeGE1, the second gate electrode GE2, and the third gate electrode GE3 maybe unitary. In an exemplary embodiment, although not illustrated, a padportion (e.g., an end portion) of the gate line GL may have a greaterplanar area than a planar area of another portion thereof so as toproperly contact another layer or an external driving circuit.

The gate line GL may include or be formed of aluminum (Al) or alloysthereof, silver (Ag) or alloys thereof, copper (Cu) or alloys thereof,and/or molybdenum (Mo) or alloys thereof. In an exemplary embodiment,the gate line GL may include or be formed of one of chromium (Cr),tantalum (Ta), and titanium (Ti). In an exemplary embodiment, the gateline GL may have a multilayer structure including at least twoconductive layers that have different physical properties from oneanother.

The first gate electrode GE1 may be a portion of the gate line GL.Dissimilarly thereto, the first gate electrode GE1 may have a shapeprotruding from the gate line GL. As illustrated in FIGS. 1 and 2, thefirst gate electrode GE1 overlaps the first semiconductor layer 321. Thefirst gate electrode GE1 may include the same material and may have thesame structure (multilayer structure) as those of the gate line GL. Thefirst gate electrode GE1 and the gate line GL may be simultaneouslyformed in the same process.

The second gate electrode GE2 may be a portion of the gate line GL.Dissimilarly thereto, the second gate electrode GE2 may have a shapeprotruding from the gate line GL. As illustrated in FIGS. 1 and 3, thesecond gate electrode GE2 overlaps the second semiconductor layer 322.The second gate electrode GE2 may include the same material and may havethe same structure (multilayer structure) as those of the gate line GL.The second gate electrode GE2 and the gate line GL may be simultaneouslyformed in the same process.

The third gate electrode GE3 may be a portion of the gate line GL.Dissimilarly thereto, the third gate electrode GE3 may have a shapeprotruding from the gate line GL. As illustrated in FIGS. 1 and 4, thethird gate electrode GE3 overlaps the third semiconductor layer 323. Thethird gate electrode GE3 may include the same material and may have thesame structure (multilayer structure) as those of the gate line GL. Thethird gate electrode GE3 and the gate line GL may be simultaneouslyformed in the same process.

The first storage electrode 751, as illustrated in FIG. 1, encloses thefirst sub-pixel electrode PE1. In such an exemplary embodiment, thefirst storage electrode 751 may overlap an edge portion of the firstsub-pixel electrode PE1. A first storage voltage Vcst1 is applied to thefirst storage electrode 751. The first storage voltage Vcst1 may have avoltage level the same as that of a common voltage Vcom. The firststorage electrode 751 may include the same material and have the samestructure (multilayer structure) as those of the gate line GL. The firststorage electrode 751 and the gate line GL may be simultaneously formedin the same process.

The first storage electrode 751 is connected to the storage line 750.The storage line 750, as illustrated in FIG. 1, is disposed between thefirst sub-pixel area P1 and the second sub-pixel area P2. The storageline 750 is substantially parallel to the gate line GL. The firststorage voltage Vcst1 is applied to the storage line 750. In such anexemplary embodiment, the first storage electrode 751 and the storageline 750 may be unitary. The storage line 750 may include the samematerial and have the same structure (multilayer structure) as those ofthe gate line GL. In an exemplary embodiment, the storage line 750 andthe gate line GL may be simultaneously formed in the same process.

The second storage electrode 752, as illustrated in FIG. 1, encloses thesecond sub-pixel electrode PE2. In such an exemplary embodiment, thesecond storage electrode 752 overlaps an edge portion of the secondsub-pixel electrode PE2. A second storage voltage Vcst2 is applied tothe second storage electrode 752. The second storage voltage Vcst2 mayhave a voltage level the same as that of the common voltage Vcom. In anexemplary embodiment, the second storage electrode 752 and the firststorage electrode 751 may be unitary. The second storage electrode 752may include the same material and have the same structure (multilayerstructure) as those of the gate line GL. The second storage electrode752 and the gate line GL may be simultaneously formed in the sameprocess.

The gate insulating layer 311, as illustrated in FIGS. 2 and 3, isdisposed above the gate line GL, the first gate electrode GE1, thesecond gate electrode GE2, the first storage electrode 751, the secondstorage electrode 752, and the storage line 750. In such an exemplaryembodiment, the gate insulating layer 311 is disposed over an entiresurface of the first substrate 301 including the gate line GL, the firstgate electrode GE1, the second gate electrode GE2, the first storageelectrode 751, the second storage electrode 752, and the storage line750. The gate insulating layer 311 has a gate contact hole passingthrough a portion of the gate insulating layer 311. The storage line 750is exposed through the gate contact hole. The gate insulating layer 311may include or be formed of silicon nitride (SiN_(x)) or silicon oxide(SiO_(x)), for example. The gate insulating layer 311 may have amultilayer structure including at least two insulating layers that havedifferent physical properties from one another.

The gate insulating layer 311 may include fluorine (F). For example, thegate insulating layer 311 may include fluorine atoms at a concentrationof about 10¹⁸ atom/cm³ or higher. A concentration of the fluorine (F) isdecreasing, as the fluorine (F) of the gate insulating layer 311 beingmore adjacent to the first substrate 301.

The gate insulating layer 311 may include fluorine (F) at lowerconcentration, as being more adjacent to the first substrate 301. Thatis, the gate insulating layer 311 may have a fluorine (F) concentrationthat varies in the vertical (depth) direction. For example, a portion ofthe gate insulating layer 311 relatively adjacent to the first substrate301 has a relatively low concentration of fluorine (F), while anotherportion of the gate insulating layer 311 relatively distanced from thefirst substrate 301 has a relatively high concentration of fluorine (F).For example, the portion of the gate insulating layer 311 relativelyadjacent to the first substrate 301 may include fluorine atoms at aconcentration of about 10¹⁸ atom/cm³, and the another portion of thegate insulating layer 311 relatively distanced from the first substrate301 may include fluorine atoms at a concentration higher than about 10¹⁸atom/cm³⁰.

The data line DL, as illustrated in FIG. 2, is disposed above the gateinsulating layer 311. Although not illustrated, a pad portion (e.g., anend portion) of the data line DL may have a greater planar area than aplanar area of another portion thereof so as to properly contact anotherlayer or an external driving circuit.

The data line DL intersects the gate line GL and the storage line 750.Although not illustrated, a portion of the data line DL that intersectsthe gate line GL may have a smaller line width than a line width ofanother portion of the data line DL. Similarly thereto, a portion of thedata line DL that intersects the storage line 750 may have a smallerline width than a line width of another portion of the data line DL.Accordingly, a parasitic capacitance between the data line DL and thegate line GL and a capacitance between the data line DL and the storageline 750 may be reduced.

The data line DL may include or be formed of refractory metal, such asmolybdenum, chromium, tantalum, and titanium, or an alloy thereof. Thedata line DL may have a multilayer structure including a refractorymetal layer and a low-resistance conductive layer. Examples of themultilayer structure may include: a double-layer structure including achromium or molybdenum (alloy) lower layer and an aluminum (alloy) upperlayer; and a triple-layer structure including a molybdenum (alloy) lowerlayer, an aluminum (alloy) intermediate layer, and a molybdenum (alloy)upper layer. In an alternative exemplary embodiment, the data line DLmay include or be formed of any suitable metals or conductors ratherthan the aforementioned materials.

The first semiconductor layer 321, as illustrated in FIG. 2, is disposedabove the gate insulating layer 311. The first semiconductor layer 321,as illustrated in FIGS. 1 and 2, overlaps the first gate electrode GE1.The first semiconductor layer 321 may include or be formed of, forexample, amorphous silicon or polycrystalline silicon. Herein, each ofthe amorphous silicon and the polycrystalline silicon may furtherinclude hydrogen (H).

A channel area of the first semiconductor layer 321 may havesubstantially the same thickness as a thickness of a thickest portion ofa non-channel area of the first semiconductor layer 321. In other words,an upper surface of the first semiconductor layer 321 is substantiallyflat. That is, in the case that a surface of the first semiconductor 321that faces (or contacts) the gate insulating layer 311 is defined as alower surface of the first semiconductor layer 321 and a surface of thefirst semiconductor layer 321 that is opposite to the aforementionedlower surface is defined as an upper surface of the first semiconductorlayer 321, the upper surface of the first semiconductor layer 321 issubstantially flat. In an exemplary embodiment, the aforementionedchannel area of the first semiconductor layer 321 refers to an area ofthe first semiconductor layer 321 corresponding to a channel area of thefirst switching element TFT1.

The second semiconductor layer 322, as illustrated in FIG. 3, isdisposed above the gate insulating layer 311. The second semiconductorlayer 322, as illustrated in FIGS. 1 and 3, overlaps the second gateelectrode GE2. The second semiconductor layer 322 may include or beformed of the same material as that included in the first semiconductorlayer 321. The second semiconductor layer 322 and the firstsemiconductor layer 321 may be simultaneously formed in the sameprocess. As illustrated in FIG. 1, the second semiconductor layer 322and the first semiconductor layer 321 may be unitary.

A channel area of the second semiconductor layer 322 may havesubstantially the same thickness as a thickness of a thickest portion ofa non-channel area of the second semiconductor layer 322. In otherwords, an upper surface of the second semiconductor layer 322 issubstantially flat. That is, in the case that a surface of the secondsemiconductor 322 that faces (or contacts) the gate insulating layer 311is defined as a lower surface of the second semiconductor layer 322 anda surface of the second semiconductor layer 322 that is opposite to theaforementioned lower surface is defined as an upper surface of thesecond semiconductor layer 322, the upper surface of the secondsemiconductor layer 322 is substantially flat. In an exemplaryembodiment, the aforementioned channel area of the second semiconductorlayer 322 refers to an area of the second semiconductor layer 322corresponding to a channel area of the second switching element TFT2.

The third semiconductor layer 323, as illustrated in FIG. 4, is disposedabove the gate insulating layer 311. The third semiconductor layer 323,as illustrated in FIGS. 1 and 4, overlaps the third gate electrode GE3.The third semiconductor layer 323 may include the same material as thatincluded in the first semiconductor layer 321. The third semiconductorlayer 323 and the first semiconductor layer 321 may be simultaneouslyformed in the same process.

A channel area of the third semiconductor layer 323 may havesubstantially the same thickness as a thickness of a thickest portion ofa non-channel area of the third semiconductor layer 323. In other words,an upper surface of the third semiconductor layer 323 is substantiallyflat. That is, in the case that a surface of the third semiconductor 323that faces (or contacts) the gate insulating layer 311 is defined as alower surface of the third semiconductor layer 323 and a surface of thethird semiconductor layer 323 that is opposite to the aforementionedlower surface is defined as an upper surface of the third semiconductorlayer 323, the upper surface of the third semiconductor layer 323 issubstantially flat. In an exemplary embodiment, the aforementionedchannel area of the third semiconductor layer 323 refers to an area ofthe third semiconductor layer 323 corresponding to a channel area of thethird switching element TFT3.

The first and second ohmic contact layers 321 a and 321 b, asillustrated in FIG. 2, are disposed above the first semiconductor layer321. The first and second ohmic contact layers 321 a and 321 b face eachother, having the channel area of the first switching element TFT1therebetween. At least one of the first ohmic contact layer 321 a andthe second ohmic contact layer 321 b may include or be formed ofn+hydrogenated amorphous silicon doped with n-type impurities, such asphosphorus (P) or hydrogen phosphide (PH₃), at high concentration. Forexample, at least one of the first ohmic contact layer 321 a and thesecond ohmic contact layer 321 b may include impurities (phosphorus (P)or hydrogen phosphide (PH₃)) at a concentration of about 2*10²¹ atom/cm³or higher. In an alternative exemplary embodiment, at least one of thefirst ohmic contact layer 321 a and the second ohmic contact layer 321 bmay include silicide.

The first ohmic contact layer 321 a is disposed between the firstsemiconductor layer 321 and the first drain electrode DE1, between thegate insulating layer 311 and the first drain electrode DE1, and betweenthe gate insulating layer 311 and the data line DL. In other words, aportion of the first ohmic contact layer 321 a is disposed between thefirst semiconductor layer 321 and the first drain electrode DE1, anotherportion of the first ohmic contact layer 321 a is disposed between thegate insulating layer 311 and the first drain electrode DE1, and stillanother portion of the first ohmic contact layer 321 a is disposedbetween the gate insulating layer 311 and the data line DL. In such anexemplary embodiment, the portion of the first ohmic contact layer 321 abetween the gate insulating layer 311 and the first drain electrode DE1contacts the gate insulating layer 311. In addition, the portion of thefirst ohmic contact layer 321 a between the gate insulating layer 311and the data line DL contacts the gate insulating layer 311. In otherwords, a portion of the first ohmic contact layer 321 a substantiallyimmediately above the gate insulating layer 311 directly contacts thegate insulating layer 311.

The second ohmic contact layer 321 b is disposed between the firstsemiconductor layer 321 and the first source electrode SE1 and betweenthe gate insulating layer 311 and the first source electrode SE1. Inother words, a portion of the second ohmic contact layer 321 b isdisposed between the first semiconductor layer 321 and the first sourceelectrode SE1, and another portion of the second ohmic contact layer 321b is disposed between the gate insulating layer 311 and the first sourceelectrode SE1. In such an exemplary embodiment, the portion of thesecond ohmic contact layer 321 b between the gate insulating layer 311and the first source electrode SE1 contacts the gate insulating layer311. In other words, a portion of the second ohmic contact layer 321 bsubstantially immediately above the gate insulating layer 311 directlycontacts the gate insulating layer 311.

Third and fourth ohmic contact layers 322 a and 322 b, as illustrated inFIG. 3, are disposed above the second semiconductor layer 322. The thirdand fourth ohmic contact layers 322 a and 322 b face each other, havingthe channel area of the second switching element TFT2 therebetween. Thethird and fourth ohmic contact layers 322 a and 322 b may include thesame material as that included in the aforementioned first ohmic contactlayer 321 a. In an exemplary embodiment, the third ohmic contact layer322 a and the second ohmic contact layer 321 b may be unitary.

The third ohmic contact layer 322 a is disposed between the secondsemiconductor layer 322 and the second drain electrode DE2 and betweenthe gate insulating layer 311 and the second drain electrode DE2. Inother words, a portion of the third ohmic contact layer 322 a isdisposed between the second semiconductor layer 322 and the second drainelectrode DE2, and another portion of the third ohmic contact layer 322a is disposed between the gate insulating layer 311 and the second drainelectrode DE2. In such an exemplary embodiment, the portion of the thirdohmic contact layer 322 a between the gate insulating layer 311 and thesecond drain electrode DE2 contacts the gate insulating layer 311. Inother words, a portion of the third ohmic contact layer 322 asubstantially immediately above the gate insulating layer 311 directlycontacts the gate insulating layer 311.

The fourth ohmic contact layer 322 b is disposed between the secondsemiconductor layer 322 and the second source electrode SE2 and betweenthe gate insulating layer 311 and the second source electrode SE2. Inother words, a portion of the fourth ohmic contact layer 322 b isdisposed between the second semiconductor layer 322 and the secondsource electrode SE2, and another portion of the fourth ohmic contactlayer 322 b is disposed between the gate insulating layer 311 and thesecond source electrode SE2. In such an exemplary embodiment, theportion of the fourth ohmic contact layer 322 b between the gateinsulating layer 311 and the second source electrode SE2 contacts thegate insulating layer 311. In other words, a portion of the fourth ohmiccontact layer 322 b substantially immediately above the gate insulatinglayer 311 directly contacts the gate insulating layer 311.

Fifth and sixth ohmic contact layers 323 a and 323 b, as illustrated inFIG. 4, are disposed above the third semiconductor layer 323. The fifthand sixth ohmic contact layers 323 a and 323 b face each other, havingthe channel area of the third switching element TFT3 therebetween. Thefifth and sixth ohmic contact layers 323 a and 323 b may include thesame material as that included in the first ohmic contact layer 321 a.

The fifth ohmic contact layer 323 a is disposed between the thirdsemiconductor layer 323 and the third drain electrode DE3 and betweenthe gate insulating layer 311 and the third drain electrode DE3. Inother words, a portion of the fifth ohmic contact layer 323 a isdisposed between the third semiconductor layer 323 and the third drainelectrode DE3, and another portion of the fifth ohmic contact layer 323a is disposed between the gate insulating layer 311 and the third drainelectrode DE3. In such an exemplary embodiment, the portion of the fifthohmic contact layer 323 a between the gate insulating layer 311 and thethird drain electrode DE3 contacts the gate insulating layer 311. Inother words, a portion of the fifth ohmic contact layer 323 asubstantially immediately above the gate insulating layer 311 directlycontacts the gate insulating layer 311.

The sixth ohmic contact layer 323 b is disposed between the thirdsemiconductor layer 323 and the third source electrode SE3 and betweenthe gate insulating layer 311 and the third source electrode SE3. Inother words, a portion of the sixth ohmic contact layer 323 b isdisposed between the third semiconductor layer 323 and the third sourceelectrode SE3, and another portion of the sixth ohmic contact layer 323b is disposed between the gate insulating layer 311 and the third sourceelectrode SE3. In such an exemplary embodiment, the portion of the sixthohmic contact layer 323 b between the gate insulating layer 311 and thethird source electrode SE3 contacts the gate insulating layer 311. Inother words, a portion of the sixth ohmic contact layer 323 bsubstantially immediately above the gate insulating layer 311 directlycontacts the gate insulating layer 311.

The first, second, third, fourth, fifth, and sixth ohmic contact layers321 a, 321 b, 322 a, 322 b, 323 a, and 323 b may be simultaneouslyformed in the same process.

The first drain electrode DE1, as illustrated in FIG. 2, is disposedabove the first ohmic contact layer 321 a. The first drain electrodeDE1, as illustrated in FIG. 1, may have a shape protruding from the dataline DL. Although not illustrated, the first drain electrode DE1 may bea portion of the data line DL. The first drain electrode DE1 overlapsthe first semiconductor layer 321 and the first gate electrode GE1. Thefirst drain electrode DE1 may have a shape selected from an I-shape, aC-shape, and a U-shape. The first drain electrode DE1 having a U-shapeis illustrated in FIG. 1, and a protruding portion of the first drainelectrode DE1 faces toward the second sub-pixel electrode PE2. The firstdrain electrode DE1 may include the same material and may have the samestructure (multilayer structure) as those of the data line DL. The firstdrain electrode DE1 and the data line DL may be simultaneously formed inthe same process.

The first drain electrode DE1 and the data line DL are disposed alongthe first ohmic contact layer 321 a. A data transmitting wiring whichincludes the first drain electrode DE1 and the data line DL may have thesame shape as that of the first ohmic contact layer 321 a.

The first source electrode SE1, as illustrated in FIG. 2, is disposedabove the second ohmic contact layer 321 b. The first source electrodeSE1 overlaps the first semiconductor layer 321 and the first gateelectrode GE1. The first source electrode SE1 is connected to the firstsub-pixel electrode PE1 through a first connecting electrode 181. Thefirst source electrode SE1 may include the same material and may havethe same structure (multilayer structure) as those of the data line DL.The first source electrode SE1 and the data line DL may besimultaneously formed in the same process.

The first source electrode SE1 is disposed along the second ohmiccontact layer 321 b. The first source electrode SE1 may havesubstantially the same shape as that of the first ohmic contact layer321 a.

The second drain electrode DE2, as illustrated in FIG. 3, is disposedabove the third ohmic contact layer 322 a. The second drain electrodeDE2 and the first drain electrode DE1 are unitary. The second drainelectrode DE2 overlaps the second semiconductor layer 322 and the secondgate electrode GE2. The second drain electrode DE2 may have a shapeselected from an I-shape, a C-shape, and a U-shape. The second drainelectrode DE2 having a U-shape is illustrated in FIG. 1, and aprotruding portion of the second drain electrode DE2 faces toward thefirst sub-pixel electrode PE1. The second drain electrode DE2 mayinclude the same material and may have the same structure (multilayerstructure) as those of the data line DL. In an exemplary embodiment, thesecond drain electrode DE2 and the data line DL may be simultaneouslyformed in the same process.

The second drain electrode DE2 is disposed along the third ohmic contactlayer 322 a. The second drain electrode DE2 may have substantially thesame shape as that of the third ohmic contact layer 322 a.

The second source electrode SE2, as illustrated in FIG. 3, is disposedabove the fourth ohmic contact layer 322 b. The second source electrodeSE2 overlaps the second semiconductor layer 322 and the second gateelectrode GE2. The second source electrode SE2 is connected to thesecond sub-pixel electrode PE2 through a second connecting electrode182. The second source electrode SE2 may include the same material andmay have the same structure (multilayer structure) as those of the dataline DL. The second source electrode SE2 and the data line DL may besimultaneously formed in the same process.

The second source electrode SE2 is disposed along the fourth ohmiccontact layer 322 b. The second source electrode SE2 may havesubstantially the same shape as that of the fourth ohmic contact layer322 b.

The third drain electrode DE3, as illustrated in FIG. 4, is disposedabove the fifth ohmic contact layer 323 a. The third drain electrode DE3and the second source electrode SE2 are unitary. The third drainelectrode DE3 overlaps the third semiconductor layer 323 and the thirdgate electrode GE3. The third drain electrode DE3 may have a shapeselected from an I-shape, a C-shape, and a U-shape. The third drainelectrode DE3 having an I-shape is illustrated in FIG. 1. The thirddrain electrode DE3 may include the same material and may have the samestructure (multilayer structure) as those of the data line DL. In anexemplary embodiment, the third drain electrode DE3 and the data line DLmay be simultaneously formed in the same process.

The third drain electrode DE3 is disposed along the fifth ohmic contactlayer 323 a. The third drain electrode DE3 may have substantially thesame shape as that of the fifth ohmic contact layer 323 a.

The third source electrode SE3, as illustrated in FIG. 4, is disposedabove the sixth ohmic contact layer 323 b. The third source electrodeSE3 overlaps the third semiconductor layer 323 and the third gateelectrode GE3. The third source electrode SE3 is connected to thestorage line 750 through a third connecting electrode 183. The thirdsource electrode SE3 may include the same material and may have the samestructure (multilayer structure) as those of the aforementioned dataline DL. In an exemplary embodiment, the third source electrode SE3 andthe data line DL may be simultaneously formed in the same process.

The third source electrode SE3 is disposed along the sixth ohmic contactlayer 323 b. The third source electrode SE3 may have substantially thesame shape as that of the sixth ohmic contact layer 323 b.

The passivation layer 320, as illustrated in FIGS. 2, 3, and 4, isdisposed above the data line DL, the first drain electrode DE1, thesecond drain electrode DE2, the third drain electrode DE3, the firstsource electrode SE1, the second source electrode SE2, and the thirdsource electrode SE3. In such an exemplary embodiment, the passivationlayer 320 is disposed over the entire surface of the first substrate 301including the data line DL, the first drain electrode DE1, the seconddrain electrode DE2, the third drain electrode DE3, the first sourceelectrode SE1, the second source electrode SE2, and the third sourceelectrode SE3. The passivation layer 320 has first, second, and thirdlower contact holes passing through a portion of the passivation layer320. A top surface of the first source electrode SE1 is externallyexposed through the first lower contact hole, a top surface of thesecond source electrode SE2 is externally exposed through the secondlower contact hole, and a top surface and a side surface of the thirdsource electrode SE3 is externally exposed through the third lowercontact hole.

The passivation layer 320 may include or be formed of an inorganicinsulating material such as silicon nitride (SiN_(x)) or silicon oxide(SiO_(x)). The passivation layer 320 may include or be formed of anorganic insulating material. In such an exemplary embodiment, an organicinsulating material having photosensitivity and having a dielectricconstant of about 4.0 may be used. In an alternative exemplaryembodiment, the passivation layer 320 may have a double-layer structureincluding a lower inorganic layer and an upper organic layer, which hasbeen found to impart desirable insulating properties and also to preventdamage to exposed portions of the first, second, and third semiconductorlayers 321, 322, and 323. The passivation layer 320 may have a thicknessgreater than or equal to about 5000 Å, for example, in a range of about6000 Å to about 8000 Å.

The color filter 354, as illustrated in FIGS. 2, 3, and 4, is disposedabove the passivation layer 320. The color filter 354 is disposed in thefirst sub-pixel area P1 and the second sub-pixel area P2. In addition,the color filter 354 may further be disposed above the passivation layer320 between the first sub-pixel area P1 and the second sub-pixel areaP2. In such an exemplary embodiment, the color filter 354 may be removedin the first, second, and third contact holes CH, CH2, and CH3. In anexemplary embodiment, an edge portion of one of the color filters 354may overlap an edge portion of another of the color filters 354 that isadjacent thereto. Color filters 354 having the same color arerespectively disposed in the first sub-pixel area P1 and the secondsub-pixel area P2 that are included in the same pixel. The color filter354 may include or be formed of a photosensitive organic material.

The capping layer 391, as illustrated in FIGS. 2, 3, and 4, is disposedabove the color filter 354. The capping layer 391 is configured toprevent permeation of undesirable materials, generated in the colorfilter 354, into the liquid crystal layer 333. The capping layer 391 hasfirst, second, and third upper contact holes passing therethrough. Thefirst upper contact hole is disposed above the first lower contact holewhich exposes the first source electrode SE1. The first upper contacthole is connected to the first lower contact hole, thereby forming thefirst contact hole CH1. The second upper contact hole is disposed abovethe second lower contact hole which exposes the second source electrodeSE2. The second upper contact hole is connected to the second lowercontact hole, thereby forming the second contact hole CH2. The thirdupper contact hole is disposed above the third lower contact hole whichexposes the third source electrode SE3. The third upper contact hole,the third lower contact hole, and the gate contact hole are connected toone another, thereby forming the third contact hole CH3. The cappinglayer 391 may include or be formed of silicon nitride or silicon oxide.

The first sub-pixel electrode PE1, as illustrated in FIGS. 1 and 2, isdisposed in the first sub-pixel area P1. In such an exemplaryembodiment, the first sub-pixel electrode PE1 is disposed above thecapping layer 391. The first sub-pixel electrode PE1 is connected to thefirst source electrode SE1 through the first contact hole CH1.

The first sub-pixel electrode PE1 may include or be formed of atransparent conductive material, such as indium tin oxide (“ITO”) orindium zinc oxide (“IZO”). Herein, ITO may be a polycrystalline ormonocrystalline material, and IZO may be a polycrystalline ormonocrystalline material as well. In an alternative exemplaryembodiment, IZO may be an amorphous material.

Hereinafter, the first sub-pixel electrode PE1 will be described indetail with reference to FIG. 5.

FIG. 5 illustrates the first sub-pixel electrode PE1 of FIG. 2.

The first sub-pixel electrode PE1, as illustrated in FIG. 5, includes astem electrode 613 and a plurality of branch electrodes 601 a, 601 b,601 c, and 601 d. The stem electrode 613 and the branch electrodes 601a, 601 b, 601 c, and 601 d may be unitary.

The stem electrode 613 divides the first sub-pixel area P1 into aplurality of domains. For example, the stem electrode 613 includes ahorizontal portion 611 and a vertical portion 612 which intersect eachother. The horizontal portion 611 divides the first sub-pixel area P1into two domains, and the vertical portion 612 divides each of thedivided two domains into another two smaller domains. A pixel area P maybe divided into four domains A, B, C, and D by the stem electrode 613which includes the horizontal portion 611 and the vertical portion 612.

The branch electrodes 601 a, 601 b, 601 c, and 601 d include first,second, third, and fourth branch electrodes 601 a, 601 b, 601 c, and 601d extending from the stem electrode 613 into different directions,respectively. That is, the first, second, third, and fourth branchelectrodes 601 a, 601 b, 601 c, and 601 d extend from the stem electrode613 into respective ones of the domains A, B, C, and D. For example, thefirst branch electrode 601 a is disposed in the first domain A, thesecond branch electrode 601 b is disposed in the second domain B, thethird branch electrode 601 c is disposed in the third domain C, and thefourth branch electrode 601 d is disposed in the fourth domain D.

The first branch electrode 601 a and the second branch electrode 601 bmay be a line symmetric with respect to the vertical portion 612, andthe third branch electrode 601 c and the fourth branch electrode 601 dmay be a line symmetric with respect to the vertical portion 612. Inaddition, the first branch electrode 601 a and the fourth branchelectrode 601 d may be a line symmetric with respect to the horizontalportion 611, and the second branch electrode 601 b and the third branchelectrode 601 c may be a line symmetric with respect to the horizontalportion 611.

The first branch electrode 601 a may include a plurality of first branchelectrodes 601 a in the first domain A, and in such an exemplaryembodiment, the plurality of first branch electrodes 601 a are alignedparallel to one another. In this regard, a part of the first branchelectrodes 601 a connected to the horizontal portion 611 in the firstdomain A may extend in a diagonal direction with respect to thehorizontal portion 611. Further, the other of the first branchelectrodes 601 a connected to the vertical portion 612 in the firstdomain A may extend in a diagonal direction with respect to the verticalportion 612.

The second branch electrode 601 b may include a plurality of secondbranch electrodes 601 b in the second domain B, and in such an exemplaryembodiment, the plurality of second branch electrodes 601 b are alignedparallel to one another. In this regard, a part of the second branchelectrodes 601 b connected to the horizontal portion 611 in the seconddomain B may extend in a diagonal direction with respect to thehorizontal portion 611. Further, the other of the second branchelectrodes 601 b connected to the vertical portion 612 in the seconddomain B may extend in a diagonal direction with respect to the verticalportion 612.

The third branch electrode 601 c may include a plurality of third branchelectrodes 601 c in the third domain C, and in such an exemplaryembodiment, the plurality of third branch electrodes 601 c are alignedparallel to one another. In this regard, a part of the third branchelectrodes 601 c connected to the horizontal portion 611 in the thirddomain C may extend in a diagonal direction with respect to thehorizontal portion 611. Further, the other of the third branchelectrodes 601 c connected to the vertical portion 612 in the thirddomain C may extend in a diagonal direction with respect to the verticalportion 612.

The fourth branch electrode 601 d may include a plurality of fourthbranch electrodes 601 d in the fourth domain D, and in such an exemplaryembodiment, the plurality of fourth branch electrodes 601 d are alignedparallel to one another. In this regard, a part of the fourth branchelectrodes 601 d connected to the horizontal portion 611 in the fourthdomain D may extend in a diagonal direction with respect to thehorizontal portion 611. Further, the other of the fourth branchelectrodes 601 d connected to the vertical portion 612 in the fourthdomain D may extend in a diagonal direction with respect to the verticalportion 612.

The aforementioned stem electrode 613 may further include a firstconnecting portion 614 a and a second connecting portion 614 b. Thefirst connecting portion 614 a is connected to one end of the horizontalportion 611, and the second connecting portion 614 b is connected toanother end of the horizontal portion 611. The first connecting portion614 a and the second connecting portion 614 b may be aligned parallel tothe vertical portion 612. The first connecting portion 614 a and thesecond connecting portion 614 b may be unitary with the stem electrode613.

End portions of at least two of the first branch electrodes 601 a in thefirst domain A and end portions of at least two of the fourth branchelectrodes 601 d in the fourth domain D may be connected to one anotherby the second connecting portion 614 b. Similarly thereto, end portionsof at least two of the second branch electrodes 601 b in the seconddomain B and end portions of at least two of the third branch electrodes601 c in the third domain C may be connected to one another by the firstconnecting portion 614 a.

In addition, although not illustrated, end portions of at least two ofthe first branch electrodes 601 a in the first domain A and end portionsof at least two of the second branch electrodes 601 b in the seconddomain B may be connected to another connecting portion. Further, endportions of at least two of the third branch electrodes 601 c in thethird domain C and end portions of at least two of the fourth branchelectrodes 601 d in the fourth domain D may be connected to anotherconnecting portion.

The first sub-pixel electrode PE1 and the first storage electrode 751may overlap each other. For example, an edge portion of the firstsub-pixel electrode PE1 may be disposed above the first storageelectrode 751.

A connecting portion between the first switching element TFT1 and thefirst sub-pixel electrode PE1 may be disposed between the gate line GLand the first sub-pixel electrode PE1. In other words, the first contacthole CH1 may be disposed between the gate line GL and the firstsub-pixel electrode PE1.

The second sub-pixel electrode PE2, as illustrated in FIGS. 1 and 3, isdisposed in the second sub-pixel area P2. In such an exemplaryembodiment, the second sub-pixel electrode PE2 is disposed above thecapping layer 391. The second sub-pixel electrode PE2 is connected tothe second source electrode SE2 through the second contact hole CH2. Thesecond sub-pixel electrode PE2 may include or be formed of the samematerial as that included in the first sub-pixel electrode PE1. That is,the second sub-pixel electrode PE2 and the first sub-pixel electrode PE1may be simultaneously provided in the same process.

The second sub-pixel electrode PE2 may have substantially the sameconfiguration as that of the first sub-pixel electrode PE1. For example,the second sub-pixel electrode PE2 includes a stem electrode thatdivides the second sub-pixel area P2 into a plurality of domains andbranch electrodes extending from the stem electrode into correspondingones of the domains. In addition, the second sub-pixel electrode PE2 mayfurther include a first connecting portion and a second connectingportion. Since the stem electrode, the branch electrode, the firstconnecting portion, and the second connecting portion included in thesecond sub-pixel electrode PE2 are the same as those included in thefirst sub-pixel electrode PE1, descriptions pertaining thereto will makereference to FIG. 5 and the related descriptions.

The second sub-pixel electrode PE2 may have a planar area greater thanor equal to that of the first sub-pixel electrode PE1. In an exemplaryembodiment, the planar area of the second sub-pixel electrode PE2 may befrom one time to two times the planar area of the first sub-pixelelectrode PE1.

The second sub-pixel electrode PE2 and the second storage electrode 752may overlap each other. For example, an edge portion of the secondsub-pixel electrode PE2 may be disposed above the second storageelectrode 752.

A connecting portion between the second switching element TFT2 and thesecond sub-pixel electrode PE2 may be disposed between the gate line GLand the second sub-pixel electrode PE2. In other words, the secondcontact hole CH2 may be defined between the gate line GL and the secondsub-pixel electrode PE2.

A connecting portion between the third switching element TFT3 and thestorage line 750 may be disposed between the gate line GL and the firstsub-pixel electrode PE1. In other words, the third contact hole CH3 maybe defined between the gate line GL and the first sub-pixel electrodePE1.

The light blocking layer 376, as illustrated in FIGS. 2, 3, and 4, isdisposed above the second substrate 302. The light blocking layer 376 isdisposed above a portion of the second substrate 302, except the firstsub-pixel area P1 and the second sub-pixel area P2. In an alternativeexemplary embodiment, the light blocking layer 376 may be disposed abovethe first substrate 301. The light blocking layer 376 may be referred toas a black matrix.

The overcoat layer 722 is disposed above the light blocking layer 376.In such an exemplary embodiment, the overcoat layer 722 may be disposedover an entire surface of the second substrate 302 including the lightblocking layer 376. The overcoat layer 722 serves to significantlyreduce (i.e., minimize) a height difference among elements between theovercoat layer 722 and the second substrate 302, for example, amongelements of the second substrate 302 such as the aforementioned lightblocking layer 376. The overcoat layer 722 may be omitted.

The common electrode 330 is disposed above the overcoat layer 722. Insuch an exemplary embodiment, the common electrode 330 may be disposedover the entire surface of the second substrate 302 including theovercoat layer 722. However, in an alternative exemplary embodiment, thecommon electrode 330 may be disposed above portions of the overcoatlayer 722 to correspond to the first sub-pixel area P1 and the secondsub-pixel area P2. The common voltage Vcom is applied to the commonelectrode 330.

Although not illustrated, an exemplary embodiment of the LCD device mayfurther include a first polarizer and a second polarizer. In the casethat a surface of the first substrate 301 and a surface of the secondsubstrate 302 that face each other are defined as upper surfaces of thecorresponding substrates, respectively, and surfaces opposite to theupper surfaces are defined as lower surfaces of the correspondingsubstrates, respectively, the aforementioned first polarizer is disposedabove the lower surface of the first substrate 301, and the secondpolarizer is disposed above the lower surface of the second substrate302.

A transmission axis of the first polarizer is perpendicular to atransmission axis of the second polarizer, and one of the transmissionaxes thereof is oriented parallel to the gate line GL. In an alternativeexemplary embodiment, the LCD device may only include one of the firstpolarizer and the second polarizer.

In an exemplary embodiment, although not illustrated, the LCD device mayfurther include a shielding electrode. The shielding electrode may bedisposed above the capping layer 391 to overlap the data line DL. Forexample, the shielding electrode may have the same shape as that of thedata line DL and may be disposed along the data line DL. The shieldingelectrode may include or be formed of a material the same as thatincluded in the first sub-pixel electrode PE1. The common voltage Vcommay be applied to the shielding electrode. The shielding electrode isconfigured to prevent formation of an electric field between the dataline DL and the sub-pixel electrode, for example, the first and secondsub-pixel electrodes PE1 and PE2. In such an exemplary embodiment, theshielding electrode and the common electrode 330 have an equivalentelectric potential such that light transmitted through the liquidcrystal layer between the shielding electrode and the common electrode330 is shielded by the second polarizer. Accordingly, light leakage maybe significantly reduced or prevented at a portion corresponding to thedata line DL.

The first substrate 301 and the second substrate 302 are insulatingsubstrates that include or are formed of glass or plastic.

The liquid crystal layer between the first substrate 301 and the secondsubstrate 302 include liquid crystal molecules. The liquid crystalmolecules may have a negative dielectric constant and may be homeotropicliquid crystal molecules.

In an exemplary embodiment, the first storage electrode 751 in one pixel(hereinafter, a first pixel) may be connected to the second storageelectrode 752 in another pixel (hereinafter, a second pixel) that isadjacent to the first pixel, which will be described further in detailwith reference to FIG. 6.

FIG. 6 is a view illustrating two adjacent pixels having a structuredescribed in FIG. 1. A portion of the first pixel and a portion of thesecond pixel are illustrated in FIG. 6. In an exemplary embodiment, thefirst pixel and the second pixel have the same structure as that of thepixel illustrated in FIG. 1.

As illustrated in FIG. 6, the first storage electrode 751 in the firstpixel PX1 may be connected to the second storage electrode 752 in thesecond pixel PX2. For example, the first storage electrode 751 in thefirst pixel PX1 and the second storage electrode 752 in the second pixelPX2 that are adjacent to each other between two adjacent ones of thegate lines GL and GL′ may be connected to each other. In such anexemplary embodiment, the first storage electrode 751 of the first pixelPX1 and the second storage electrode 752 of the second pixel PX2 may beunitary.

FIGS. 7A, 7B, 7C, 7D, 7E, 7F, 7G, 7H, 7I, 7J, 7K, 7L, 7M, 7N, 7O, and 7Pare cross-sectional views illustrating a process of manufacturing an LCDdevice according to an exemplary embodiment. FIGS. 7A, 7B, 7C, 7D, 7E,7F, 7G, 7H, 7I, 7J, 7K, 7L, 7M, 7N, 7O, and 7P illustratecross-sectional views taken along line I-I′ of FIG. 1.

First, although not illustrated, a gate metal layer is deposited overthe entire surface of the first substrate 301. The gate metal layer maybe deposited by a physical vapor deposition (“PVD”) method such assputtering.

Subsequently, the aforementioned gate metal layer is patterned through aphotolithography process such that the first gate electrode GE1, thestorage line 750, and the first storage electrode 751 are formed abovethe first substrate 301 as illustrated in FIG. 7A. In an exemplaryembodiment, although not illustrated, the gate line GL, the second gateelectrode GE2, the third gate electrode GE3, and the second storageelectrode 752 are also formed above the first substrate 301 when thegate metal layer is patterned.

The gate metal layer may be removed by a wet-etching method using anetching solution.

The gate metal layer may include or be formed of a material included inthe aforementioned gate line GL.

Subsequently, as illustrated in FIG. 7B, the gate insulating layer 311is deposited over the entire surface of the first substrate 301including the gate line GL, the first gate electrode GE1, the storageline 750, the first storage electrode 751, the second gate electrodeGE2, the third gate electrode GE3, and the second storage electrode 752.The gate insulating layer 311 may be deposited by a chemical vapordeposition (“CVD”) method.

The gate insulating layer 311 may include or be formed of a materialincluded in the aforementioned gate insulating layer 311.

Subsequently, as illustrated in FIG. 7C, a semiconductor material 420 isformed above the gate insulating layer 311. The semiconductor material420 is deposited over the entire surface of the first substrate 301including the gate insulating layer 311. The semiconductor material 420may be deposited by a chemical vapor deposition (CVD) method. Thesemiconductor material 420 may include or be formed of a materialincluded in the first semiconductor layer 321.

Subsequently, a photoresist PR is formed above the semiconductormaterial 420. The photoresist PR is coated over the entire surface ofthe first substrate 301 including the semiconductor material 420.

Subsequently, a mask M is disposed above the photoresist PR. The mask Mhas a transmissive area TA through which light is transmitted, ablocking area BA through which light is blocked, and a half-transmissivearea HTA through which light is partially transmitted. Thehalf-transmissive area HTA may include a plurality of slits or asemi-transparent layer. In such an exemplary embodiment, a lighttransmittance of the half-transmissive area HTA is lower than a lighttransmittance of the transmissive area TA. For example, the lighttransmittance of the half-transmissive area HTA may be about half thelight transmittance of the transmissive area TA.

Subsequently, light, e.g., ultraviolet light, is irradiated in aselective manner to the photoresist PR through the mask M such that thephotoresist PR is exposed. In the case that the photoresist PR that isexposed is developed, a first photoresist pattern PP1 and a secondphotoresist pattern PP2, which have difference thicknesses, are formedabove the semiconductor material 420 as illustrated in FIG. 7D. Thesecond photoresist pattern PP2 has a smaller thickness than that of thefirst photoresist pattern PP1. For example, the thickness of the secondphotoresist pattern PP2 may be about half the thickness of the firstphotoresist pattern PP1.

The first photoresist pattern PP1 is disposed above a portion of thesemiconductor material 420 corresponding to the blocking area BA of thepattern mask M, and the second photoresist pattern PP2 is disposed abovea portion of the semiconductor material 420 corresponding to thehalf-transmissive area HTA of the mask M. In other words, the firstphotoresist pattern PP1 and the second photoresist pattern PP2 aredisposed to correspond to an area of the first semiconductor layer 321to be formed later. In such an exemplary embodiment, the firstphotoresist pattern PP1 is disposed to correspond to the channel area ofthe first switching element TFT1 of the first semiconductor layer 321.

A portion of the photoresist PR corresponding to the transmissive areaTA of the mask M is completely removed.

Although not illustrated, through a developing process of theaforementioned photoresist PR, another first and second photoresistpatterns and still another first and second photoresist patterns areformed above the semiconductor material 420. Each of the another firstphotoresist pattern and the still another first photoresist pattern havesubstantially the same thickness as that of the aforementioned firstphotoresist pattern PP1, and each of the another second photoresistpattern and the still another second photoresist pattern havesubstantially the same thickness as that of the second photoresistpattern PP2. The another first and second photoresist patterns aredisposed to correspond to an area of the second semiconductor layer 322to be formed later, and the still another first and second photoresistpatterns are disposed to correspond to an area of the thirdsemiconductor layer 323 to be formed later. In such an exemplaryembodiment, the another first photoresist pattern is disposed tocorrespond to the channel area of the second switching element TFT2 ofthe second semiconductor layer 322, and the still another secondphotoresist pattern is disposed to correspond to the channel area of thethird switching element TFT3 of the third semiconductor layer 323.

Subsequently, in the state that the first and second photoresistpatterns PP1 and PP2 are formed, the semiconductor material 420 isetched using the first and second photoresist patterns PP1 and PP2 as amask. In such an exemplary embodiment, as illustrated in FIG. 7E, thefirst semiconductor layer 321 which overlaps the first gate electrodeGE1 is formed above the gate insulating layer 311. Although notillustrated, in the aforementioned etching process of the semiconductormaterial 420, the second semiconductor layer 322 and the thirdsemiconductor layer 323 are also formed above the gate insulating layer311.

Subsequently, as illustrated in FIG. 7F, an ashing process is performed.In the ashing process, the thickness of the first photoresist patternPP1 and the thickness of the second photoresist pattern PP2 are reducedby the same level. In such an exemplary embodiment, the ashing processis performed until the second photoresist pattern PP2, having arelatively smaller thickness, is completely removed. That is, the ashingprocess ends when the second photoresist pattern PP2 is completelyremoved.

As the second photoresist pattern PP2 is removed, the non-channel areaof the first semiconductor layer 321 therebelow is exposed. In anexemplary embodiment, as a portion of the first photoresist PP1 isremoved in the ashing process, the thickness of the first photoresistpattern PP1 is reduced. Hereinafter, the first photoresist pattern PP1after ashing is defined as a third photoresist pattern PP3. The thirdphotoresist pattern PP3 is disposed to correspond to the channel area ofthe first semiconductor layer 321. Although not illustrated, through theashing process, another third photoresist patterns are disposed tocorrespond to the channel area of the second semiconductor layer 322 andthe channel area of the third semiconductor layer 323.

Subsequently, a hydrophobization process is performed on the thirdphotoresist pattern PP3. To this end, as in an example illustrated inFIG. 7G, the third photoresist pattern PP3 may be exposed to NF₃. Forexample, NF₃ may be applied over the entire surface of the firstsubstrate 301 including the third photoresist pattern PP3. In such anexemplary embodiment, NF₃ may be provided as gas or plasma. The thirdphotoresist pattern PP3 to which NF₃ is applied is transformed into afluorinated resist. Accordingly, a surface of the third photoresistpattern PP3 is hydrophobizated.

In an exemplary embodiment, NF₃ that is applied in the aforementionedhydrophobization process of the third photoresist pattern PP3 is alsoapplied to the gate insulating layer 311, and thus the gate insulatinglayer 311 may include fluorine (F). In such an exemplary embodiment, asbeing more adjacent to the first substrate 301, the gate insulatinglayer 311 includes fluorine (F) at lower concentration. That is, thegate insulating layer 311 has a fluorine (F) concentration that variesin the vertical direction. For example, a portion of the gate insulatinglayer 311 relatively adjacent to the first substrate 301 has arelatively low concentration of fluorine (F), and another portion of thegate insulating layer 311 relatively distanced from the first substrate301 which is exposed to the NF3 has a relatively high concentration offluorine (F). For example, the portion of the gate insulating layer 311relatively adjacent to the first substrate 301 may include fluorineatoms at a concentration of about 10¹⁸ atom/cm³, and the another portionof the gate insulating layer 311 relatively distanced from the firstsubstrate 301 may include fluorine atoms at a concentration higher thanabout 10¹⁸ atom/cm³.

Subsequently, as illustrated in FIG. 7H, an impurity semiconductormaterial 450 is deposited over the entire surface of the first substrate301 excluding the third photoresist pattern PP3 that is hydrophobizated.The impurity semiconductor material 450 may include or be formed of amaterial included in the aforementioned first ohmic contact layer 321 a.In such an exemplary embodiment, the impurity semiconductor material450, as illustrated in FIG. 7H, is not deposited above the thirdphotoresist pattern PP3, which is because the surface of the thirdphotoresist pattern PP3 has hydrophobic characteristics. Accordingly,the impurity semiconductor material 450 is deposited in a selectivemanner above the first substrate 301, e.g., above the gate insulatinglayer 311 and in the non-channel area of the first semiconductor layer321, except an area corresponding to the third photoresist pattern PP3.

As such, the impurity semiconductor material 450 is not be formed in thechannel area of the first semiconductor layer 321 due to the thirdphotoresist pattern PP3 that is hydrophobizated. Although notillustrated, the third photoresist pattern PP3 that is hydrophobizatedis also disposed in the channel area of the second semiconductor layer322 and the channel area of the third semiconductor layer 323, and thusthe impurity semiconductor material 450 is not formed in the channelarea of the second semiconductor layer 322 and the channel area of thethird semiconductor layer 323. Accordingly, in the deposition process ofthe impurity semiconductor material 450, impurities (e.g., phosphorus(P)) of the impurity semiconductor material 450 may be prevented fromdiffusing into the channel areas of respective ones of the first,second, and third semiconductor layers 321, 322, and 323.

Subsequently, as illustrated in FIG. 7I, the third photoresist patternPP3 is removed. As the third photoresist pattern PP3 is removed, thechannel area of the first semiconductor layer 321 therebelow is exposed.The third photoresist pattern PP3 may be removed by a strip solution.The strip solution may include ethylene carbonate. Although notillustrated, the third photoresist pattern disposed in the channel areaof the second semiconductor layer 322 and the third photoresist patterndisposed in the channel area of the third semiconductor layer 323 arealso removed by the aforementioned strip solution.

Subsequently, as illustrated in FIG. 7J, a source metal layer 480 isformed above the impurity semiconductor material 450, the firstsemiconductor layer 321, the second semiconductor layer 322, and thethird semiconductor layer 323. In such an exemplary embodiment, thesource metal layer 480 is deposited over the entire surface of the firstsubstrate 301 including the impurity semiconductor material 450, thefirst semiconductor layer 321, the second semiconductor layer 322, andthe third semiconductor layer 323.

Subsequently, although not illustrated, a photoresist is coated abovethe source metal layer 480. The photoresist is coated over the entiresurface of the first substrate 301 including the source metal layer 480.

Subsequently, when the photoresist is exposed and developed, thephotoresist pattern PP is formed above the source metal layer 480 asillustrated in FIG. 7J.

Subsequently, in the state that the photoresist pattern PP is exist onthe source metal layer 480, the source metal layer 480 and the impuritysemiconductor material 450 are patterned through an etching processusing the photoresist pattern PP as a mask. In such an exemplaryembodiment, both of the source metal layer 480 and the impuritysemiconductor material 450 are removed by a wet etching method, which isattributed to the impurity semiconductor material 450 including theimpurities at high concentration. For example, the impuritysemiconductor material 450 may include impurities at a concentration ofabout 2*10²¹ atom/cm³ or higher, and the impurity semiconductor material450 including the impurities at such a high concentration may havecharacteristics substantially similar to metal and thus may be removedin the wet etching method. As such, as the impurity semiconductormaterial 450 may be removed in the wet etching method, the channel areasof respective ones of the first, second, and third semiconductor layers321, 322, and 323 may not be damaged in the wet etching process.Accordingly, upper surfaces of respective ones of the first, second, andthird semiconductor layers 321, 322, and 323 may be maintained flat.

Through such a patterning process, as illustrated in FIG. 7K, the firstohmic contact layer 321 a, the second ohmic contact layer 321 b, thefirst drain electrode DE1, and the first source electrode SE1 areformed. Although not illustrated, the third ohmic contact layer 322 a,the fourth ohmic contact layer 322 b, the fifth ohmic contact layer 323a, the sixth ohmic contact layer 323 b, the second drain electrode DE2,the second source electrode SE2, the third drain electrode DE3, and thethird source electrode SE3 are also formed through the patterningprocess.

Subsequently, as illustrated in FIG. 7L, the passivation layer 320 isdeposited over the entire surface of the first substrate 301 includingthe first drain electrode DE1, the first source electrode SE1, thesecond drain electrode DE2, the second source electrode SE2, the thirddrain electrode DE3, and the third source electrode SE3.

The passivation layer 320 may include a material included in theaforementioned passivation layer 320.

Subsequently, although not illustrated, a photosensitive organicmaterial is formed over the entire surface of the first substrate 301including the passivation layer 320.

Subsequently, as the photosensitive organic material is patternedthrough a photolithography process, the color filter 354 is formed inthe first sub-pixel area P1 and the second sub-pixel area P2 asillustrated in FIG. 7M.

Subsequently, as illustrated in FIG. 7N, the capping layer 391 isdeposited over the entire surface of the first substrate 301 includingthe color filter 354.

The capping layer 391 may include a material included in theaforementioned capping layer 391.

Subsequently, the capping layer 391 and the passivation layer 320 areremoved in a selective manner through a photolithography process suchthat the first contact hole CH1 which exposes a top surface of the firstsource electrode SE1 is defined as illustrated in FIG. 7O. In anexemplary embodiment, although not illustrated, through theaforementioned removal of the capping layer 391 and the passivationlayer 320 in a selective manner, the second contact hole CH2 whichexposes a top surface of the second source electrode SE2 is alsodefined. In addition, although not illustrated, the gate insulatinglayer 311, in addition to the capping layer 391 and the passivationlayer 320, is further removed in a selective manner such that thirdcontact hole CH3 which exposes a top surface and a side surface of thethird source electrode SE3, a side surface of the sixth ohmic contactlayer 323 b, and the storage line 750 is defined.

Subsequently, although not illustrated, a transparent metal layer isdeposited over the entire surface of the first substrate 301 includingthe capping layer 391, the first source electrode SE1, the second sourceelectrode SE2, the side surface of the third source electrode SE3, theside surface of the sixth ohmic contact layer 323 b, and the storageline 750.

The transparent metal layer may include a material included in theaforementioned first sub-pixel electrode PE1.

Subsequently, as the transparent metal layer is patterned through aphotolithography process, the first sub-pixel electrode PE1 and thefirst connecting electrode 181 are formed as illustrated in FIG. 7P. Thefirst connecting electrode 181 is connected to the first sourceelectrode SE1 through the first contact hole CH1. In an exemplaryembodiment, although not illustrated, in the aforementioned patterningprocess, the second sub-pixel electrode PE2, the second connectingelectrode 181, and the third connecting electrode 183 are also formed.The second connecting electrode 182 is connected to the second sourceelectrode SE2 through the second contact hole CH2. The third connectingelectrode 183 is connected to the side surface of the third sourceelectrode SE3, the side surface of the sixth ohmic contact layer 323 b,and the storage line 750 through the third contact hole CH3.

FIGS. 8A, 8B, 8C, 8D, and 8E are cross-sectional views illustrating aprocess of manufacturing an LCD device according to another exemplaryembodiment. FIGS. 8A, 8B, 8C, 8D, and 8E illustrate cross-sectionalviews taken along line I-I′ of FIG. 1.

Firstly, as illustrated in FIGS. 7A and 7B, the gate line GL, the firstgate electrode GE1, the storage line 750, the first storage electrode751, the second gate electrode GE2, the third gate electrode GE2, thesecond storage electrode 752, and the gate insulating layer 311 areformed.

Subsequently, as illustrated in FIG. 8A, the semiconductor material 420and the photoresist PR are sequentially formed above the gate insulatinglayer 311. The photoresist PR of FIG. 8A has a greater thickness than athickness of the photoresist PR of FIG. 7C.

Subsequently, a mask M is disposed above the photoresist PR. The mask Mhas a transmissive area TA through which light is transmitted, ablocking area BA through which light is blocked, and a half-transmissivearea HTA through which light is partially transmitted. The mask M ofFIG. 8A is the same as the mask M of FIG. 7C, and thus descriptionspertaining to the mask M of FIG. 8A will make reference to the mask M ofFIG. 7C and the related descriptions.

Subsequently, when the photoresist PR is exposed and developed using themask M of FIG. 8A, the first photoresist pattern PP1 and the secondphotoresist pattern PP2, which have different thicknesses, are formedabove the semiconductor material 420 as illustrated in FIG. 8B. Thefirst photoresist pattern PP1 and the second photoresist pattern PP2 aredisposed to correspond to an area of the first semiconductor layer 321to be formed later. In such an exemplary embodiment, the firstphotoresist pattern PP1 is disposed to correspond to the channel area ofthe first switching element TFT1 of the first semiconductor layer 321.

The second photoresist pattern PP2 has a smaller thickness than that ofthe first photoresist pattern PP1. In such an exemplary embodiment, thefirst photoresist pattern PP1 of FIG. 8B has a greater thickness thanthat of the aforementioned first photoresist pattern PP1 of FIG. 7D, andthe second photoresist pattern PP2 of FIG. 8B has a greater thicknessthan that of the aforementioned second photoresist pattern PP2 of FIG.7D.

Although not illustrated, through a developing process of thephotoresist PR illustrated in FIG. 8C, another first and secondphotoresist patterns and still another first and second photoresistpatterns are formed above the semiconductor material 420. The anotherfirst photoresist pattern is disposed to correspond to the channel areaof the second switching element TFT2 of the second semiconductor layer322, and the still another first photoresist pattern is disposed tocorrespond to the channel area of the third switching element TFT3 ofthe third semiconductor layer 323.

Subsequently, in the state that the first and second photoresistpatterns PP1 and PP2 are used as a mask, the semiconductor material 420is etched. Then, as illustrated in FIG. 8C, the first semiconductorlayer 321 which overlaps the first gate electrode GE1 is formed abovethe gate insulating layer 311. Although not illustrated, in theaforementioned etching process of the semiconductor material 420, thesecond semiconductor layer 322 and the third semiconductor layer 323 arealso formed above the gate insulating layer 311.

Subsequently, as illustrated in FIG. 8D, an ashing process is performed.In the ashing process, the thickness of the first photoresist patternPP1 and the thickness of the second photoresist pattern PP2 are reducedby the same level. In such an exemplary embodiment, the ashing processis performed until the second photoresist pattern PP2, having arelatively smaller thickness, is completely removed. That is, the ashingprocess ends when the second photoresist pattern PP2 is completelyremoved.

As the second photoresist pattern PP2 is removed, the non-channel areaof the first semiconductor layer 321 therebelow is exposed. In anexemplary embodiment, a portion of the first photoresist PP1 is removedthrough the ashing process, and accordingly, the thickness of the firstphotoresist pattern PP1 is reduced. Hereinafter, the first photoresistpattern PP1 after ashing is defined as a third photoresist pattern PP3.The third photoresist pattern PP3 is disposed to correspond to thechannel area of the first semiconductor layer 321. Although notillustrated, through the ashing process, another third photoresistpatterns are disposed to correspond to the channel area of the secondsemiconductor layer 322 and the channel area of the third semiconductorlayer 323.

The third photoresist pattern PP3 of FIG. 8D has a greater thicknessthan that of the third photoresist pattern PP3 of FIG. 7F.

Subsequently, as illustrated in FIG. 8E, an impurity semiconductormaterial 455 is deposited over the entire surface of the first substrate301 including the third photoresist pattern PP3. In such an exemplaryembodiment, as the third photoresist pattern PP3 is disposed in thechannel area of the first semiconductor layer 321, the impuritysemiconductor material 455 is not deposited in the channel area of thefirst semiconductor layer 321. The impurity semiconductor material 455may include a material included in the aforementioned first ohmiccontact layer 321 a.

As such, the impurity semiconductor material 455 is not formed in thechannel area of the first semiconductor layer 321. Although notillustrated, the third photoresist pattern PP3 is also disposed in thechannel area of the second semiconductor layer 322 and the channel areaof the third semiconductor layer 323, and accordingly the impuritysemiconductor material 455 is not formed in the channel areas ofrespective ones of the second semiconductor 322 and the thirdsemiconductor layer 323. Accordingly, in the deposition process of theimpurity semiconductor material 455, the impurities (e.g., phosphorus(P)) of the impurity semiconductor material 450 may be prevented fromdiffused into the channel areas of respective ones of the first, second,and third semiconductor layers 321, 322, and 323.

In an exemplary embodiment, as the third photoresist pattern PP3 has arelatively great thickness, an impurity semiconductor material 451deposited above the third photoresist pattern PP3 is separated from animpurity semiconductor material 450 deposited in another area. Althoughnot illustrated, an impurity semiconductor material deposited aboveother third photoresist patterns are separated from the impuritysemiconductor material 450 deposited in another area.

Subsequently, the third photoresist pattern PP3 is removed through alift-off process. In the case that the third photoresist pattern PP3 isremoved by a strip solution, the impurity semiconductor material 451deposited above the third photoresist pattern PP3 is also removed.Although not illustrated, the third photoresist pattern in the channelarea of the second semiconductor layer 322, the third photoresistpattern in the channel area of the third semiconductor layer 323, andthe impurity semiconductor material deposited above each of the thirdphotoresist patterns are also removed by the aforementioned stripsolution.

As the third photoresist pattern PP3 is removed, the channel area of thefirst semiconductor layer 321 therebelow is exposed as illustrated inFIG. 7I. Although not illustrated, as other third photoresist patternsare removed, the channel area of the second semiconductor layer 322 andthe channel area of the third semiconductor layer 323 are also exposed.

Subsequently, as illustrated in FIGS. 7J, 7K, 7L, 7M, 7N, 7O, and 7P,the first drain electrode DE1, the first source electrode SE1, thesecond drain electrode DE2, the second source electrode SE2, the thirddrain electrode DE3, the third source electrode SE3, the first ohmiccontact layer 321 a, the second ohmic contact layer 321 b, the thirdohmic contact layer 322 a, the fourth ohmic contact layer 322 b, thefifth ohmic contact layer 323 a, the sixth ohmic contact layer 323 b,the passivation layer 320, the color filter 354, the capping layer 391,the first contact hole CH1, the second contact hole CH2, the thirdcontact hole CH3, the first connecting electrode 181, the secondconnecting electrode 182, the third connecting electrode 183, the firstsub-pixel electrode PE1, and the second sub-pixel electrode PE2 areformed.

FIGS. 9A, 9B, 9C, 9D, 9E, 9F, 9G, and 9H are cross-sectional viewsillustrating a process of manufacturing an LCD device according to stillanother exemplary embodiment. FIGS. 9A, 9B, 9C, 9D, 9E, 9F, 9G, and 9Hillustrate cross-sectional views taken along line I-I′ of FIG. 1.

Firstly, as illustrated in FIGS. 7A and 7B, the gate line GL, the firstgate electrode GE1, the storage line 750, the first storage electrode751, the second gate electrode GE2, the third gate electrode GE2, thesecond storage electrode 752, and the gate insulating layer 311 areformed.

Subsequently, as illustrated in FIG. 9A, the semiconductor material 420and the photoresist PR are sequentially formed above the gate insulatinglayer 311.

Subsequently, a mask M is disposed above the photoresist PR. The mask Mhas a transmissive area TA through which light is transmitted and ablocking area BA through which light is blocked.

Subsequently, light, e.g., ultraviolet light, is irradiated in aselective manner to the photoresist PR through the mask M such that thephotoresist PR is exposed. In the case the photoresist PR that isexposed is developed, the first photoresist pattern PP1 is formed asillustrated in FIG. 9B. The first photoresist pattern PP1 is disposedabove a portion of the semiconductor material 420 corresponding to theblocking area BA of the mask M. In other words, the first photoresistpattern PP1 is disposed to correspond to an area of the firstsemiconductor layer 321 to be formed later. In an exemplary embodiment,the photoresist PR corresponding to the transmissive area TA of the maskM is removed.

In an exemplary embodiment, although not illustrated, through theaforementioned developing process of the photoresist PR, another firstphotoresist pattern and still another first photoresist pattern areformed above the semiconductor material 420. The another firstphotoresist pattern is disposed to correspond to an area to be formedwith the second semiconductor layer 322, and the still another firstphotoresist pattern is disposed to correspond to an area to be formedwith the third semiconductor layer 323.

Subsequently, in the state that the first photoresist pattern PP1 isexist, the semiconductor material 420 is etched using the firstphotoresist pattern PP1 as a mask. Then, as illustrated in FIG. 9C, thefirst semiconductor layer 321 which overlaps the first gate electrodeGE1 is formed above the gate insulating layer 311.

The semiconductor material 420 may be removed in a directional etchingmethod. In the case of the directional etching, an etching speed in thevertical direction is relatively high, whereas an etching speed in thehorizontal direction is relatively low. In such an exemplary embodiment,as an etching depth increases, the etching speed in the horizontaldirection gradually decreases due to crystal orientation of thesemiconductor material 450. Accordingly, as illustrated in FIG. 9C,opposite side surfaces (inclined opposite side surfaces) of the firstsemiconductor layer 321 are not covered by the first photoresist patternPP.

Although not illustrated, in the aforementioned etching process of thesemiconductor material 420, the second semiconductor layer 322 and thethird semiconductor layer 323 are also formed above the gate insulatinglayer 311. In such an exemplary embodiment, opposite side surfaces(inclined opposite side surfaces) of the second semiconductor layer 322are not covered by the first photoresist pattern PP as well, andopposite side surfaces (inclined opposite side surfaces) of the thirdsemiconductor layer 323 are not covered by the first photoresist patternPP as well.

Subsequently, as illustrated in FIG. 9D, a hydrophobization process isperformed on the first photoresist pattern PP1. Descriptions pertainingto the hydrophobization process will make reference to FIG. 7G andrelated descriptions.

Subsequently, as illustrated in FIG. 9E, the impurity semiconductormaterial 450 is deposited over the entire surface of the first substrate301 excluding the first photoresist pattern PP1 that is hydrophobizated.The impurity semiconductor material 450 may include or be formed of amaterial included in the first ohmic contact layer 321 a. In such anexemplary embodiment, the impurity semiconductor material 450, asillustrated in FIG. 9E, is not deposited above the first photoresistpattern PP1, which is because a surface of the first photoresist patternPP1 has hydrophobic characteristics. Accordingly, the impuritysemiconductor material 450 is deposited in a selective manner above thefirst substrate 301, e.g., above the gate insulating layer 311 and thenon-channel area of the first semiconductor layer 321, except a portionof the first substrate 301 corresponding to the first photoresistpattern PP1.

The impurity semiconductor material 450 may not be formed in the channelarea of the first semiconductor layer 321 due to the first photoresistpattern PP1 that is hydrophobizated. Although not illustrated, the firstphotoresist pattern PP1 that is hydrophobizated is also disposed in thechannel area of the second semiconductor layer 322 and the channel areaof the third semiconductor layer 323, and thus the impuritysemiconductor material 450 is not formed in the channel area of thesecond semiconductor layer 322 and the channel area of the thirdsemiconductor layer 323 as well. As a result, the impurity semiconductormaterial 450 may be disposed only on an inclined surface of thesemiconductor layer and may not be disposed on the flat surface of thesemiconductor layer. Accordingly, in the deposition process of theimpurity semiconductor material 450, impurities (e.g., phosphorus (P))of the impurity semiconductor material 450 may be prevented fromdiffusing into the channel areas of respective ones of the first,second, and third semiconductor layers 321, 322, and 323.

Subsequently, as illustrated in FIG. 9F, the first photoresist patternPP1 is removed. Descriptions pertaining to the process related to FIG.9F will make reference to FIG. 7I and the related descriptions. As thefirst photoresist pattern PP1 is removed, the channel area of the firstsemiconductor layer 321 therebelow is exposed. Although not illustrated,in a process of removing the first photoresist pattern, the firstphotoresist pattern in the channel area of the second semiconductorlayer 322 and the first photoresist pattern in the channel area of thethird semiconductor layer 323 are also removed.

Subsequently, as illustrated in FIG. 9G, the source metal layer 480 isformed above the impurity semiconductor material 450, the firstsemiconductor layer 321, the second semiconductor layer 322, and thethird semiconductor layer 323. Subsequently, the second photoresistpattern PP2 is formed above the source metal layer 480. Descriptionspertaining to FIG. 9G will make reference to FIG. 7J and the relateddescriptions.

In the state that the second photoresist pattern PP2 of FIG. 9G is usedas a mask, the source metal layer 480 and the impurity semiconductormaterial 450 are patterned through an etching process. In such anexemplary embodiment, both of the source metal layer 480 and theimpurity semiconductor material 450 are removed by a wet etching method,which is attributed to the impurity semiconductor material 450 includingthe impurities at high concentration. For example, the impuritysemiconductor material 450 may include impurities at a concentration ofabout 2*10²¹ atom/cm³ or higher, and the impurity semiconductor material450 including the impurities at such a high concentration may havecharacteristics substantially similar to metal and thus may be removedthrough the wet etching method.

Through the aforementioned patterning process, the first ohmic contactlayer 321 a, the second ohmic contact layer 321 b, the first drainelectrode DE1, and the first source electrode SE1 are formed asillustrated in FIG. 9H. Although not illustrated, the third ohmiccontact layer 322 a, the fourth ohmic contact layer 322 b, the fifthohmic contact layer 323 a, the sixth ohmic contact layer 323 b, thesecond drain electrode DE2, the second source electrode SE2, the thirddrain electrode DE3, and the third source electrode SE3 are also formedthrough the patterning process.

Subsequently, as illustrated in FIGS. 7I, 7J, 7K, 7L, 7M, 7N, 7O, and7P, the passivation layer 320, the color filter 354, the capping layer391, the first contact hole CH1, the second contact hole CH2, the thirdcontact hole CH3, the first connecting electrode 181, the secondconnecting electrode 182, the third connecting electrode 183, the firstsub-pixel electrode PE1, and the second sub-pixel electrode PE2 areformed.

As set forth above, according to one or more exemplary embodiments, theLCD device and the method of manufacturing the LCD device have thefollowing effects.

First, in the deposition process of the impurity semiconductor material,impurities of the impurity semiconductor material may be significantlyreduced or prevented from diffusing into the channel area of thesemiconductor layer.

Second, the impurity semiconductor material used in manufacturing of theohmic contact layer includes impurities at high concentration.Accordingly, the impurity semiconductor material may havecharacteristics substantially similar to metal and thus may be removedby a wet etching method. Therefore, in a wet etching process for formingthe source electrode, the drain electrode, and the ohmic contact layer,the channel area of the semiconductor layer may not be damaged.

From the foregoing, it will be appreciated that various embodiments inaccordance with the present disclosure have been described herein forpurposes of illustration, and that various modifications may be madewithout departing from the scope and spirit of the present teachings.Accordingly, the various embodiments disclosed herein are not intendedto be limiting of the true scope and spirit of the present teachings.

What is claimed is:
 1. A liquid crystal display device comprising: agate electrode above a substrate; a semiconductor layer which overlapsthe gate electrode; a drain electrode and a source electrode whichoverlap the semiconductor layer; an ohmic contact layer between thesemiconductor layer and the drain electrode and between thesemiconductor layer and the source electrode; a pixel electrode which isconnected to one of the drain electrode and the source electrode; and agate insulating layer between the gate electrode and the semiconductorlayer, the gate insulating layer comprising fluorine, wherein aconcentration of the fluorine is decreasing, as the fluorine of the gateinsulating layer being more adjacent to the substrate, wherein a portionof gate insulating layer between a channel area of the semiconductorlayer and the gate electrode includes a less concentration of thefluorine than other portions of gate insulating layer.
 2. The liquidcrystal display device as claimed in claim 1, wherein the ohmic contactlayer has an impurity concentration of about 2*1021 atom/cm3 or higher.3. The liquid crystal display device as claimed in claim 1, wherein theportion of the gate insulating layer does not include the fluorine. 4.The liquid crystal display device as claimed in claim 1, wherein theohmic contact layer contacts the gate insulating layer.
 5. The liquidcrystal display device as claimed in claim 4, wherein the ohmic contactlayer comprises: a first ohmic contact layer between the drain electrodeand the gate insulating layer, the first ohmic contact layer contactingthe gate insulating layer; and a second ohmic contact layer between thesource electrode and the gate insulating layer, the second ohmic contactlayer contacting the gate insulating layer.
 6. The liquid crystaldisplay device as claimed in claim 5, wherein the first ohmic contactlayer is further disposed between the gate insulating layer and the dataline which is connected to the drain electrode.
 7. The liquid crystaldisplay device as claimed in claim 1, wherein the semiconductor layerhas substantially the same thickness as a thickness of a thickestportion of a non-channel area of the semiconductor layer.
 8. The liquidcrystal display device as claimed in claim 7, wherein a second surfaceof the semiconductor layer which is opposite to a first surface of thesemiconductor layer is substantially flat, the first surface of thesemiconductor layer facing the gate insulating layer.